B&K 4070A Using the Data Modulation Mode, Data Modulation Mode Parameters, Baud Rate

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5.25 Data Modulation Mode

Introduction

The data modulation mode will digitally modulate a binary message of up to 960 bits (60 words) in length. Data is digitally modulated using FSK modulation at an adjustable baud rate. The mark and space frequencies may be independently specified from 0 Hz to 21.5 MHz with 0.01 Hz resolution. The baud rate is adjustable from 0 Hz to

130 KHz in 1 Hz steps. By specifying a Mark or Space frequency of 0 Hz, 100% digital AM modulation may also be done.

Data Modulation mode operates in a triggered burst mode. The Data Modulation mode starts by setting the output frequency to 0 Hz and awaiting a trigger condition. When a trigger condition occurs, the 4070A examines the first data bit of the binary message and sets the output frequency to the Mark frequency if the bit is a 1 or to the Space frequency if the bit is a 0. The output is held at that frequency for a period of time specified by the Baud rate field. After that, the next bit of the modulation message is processed and so on until all bits have been modulated. After the last bit has been modulated, the 4070A resets the output frequency to 0 Hz and awaits another trigger condition.

Using the Data Modulation Mode

To use the Data Modulation mode, you must do the following:

1.Switch the 4070A to Internal FSK mode by Mode, 5, 1 key combination

2.Enter the Baud rate, Mark & Space frequencies and output level on the front panel.

3.Download your data message to the 4070A through the serial port. (see below)

4.Trigger the transmission (see below)

5.Optionally store the instrument setup and message to nonvolatile memory.

Data Modulation Mode Parameters

4

1

 

 

 

 

 

 

 

 

 

Int FSK: 1,000 Hz

Mark: 1,000,000.00 Hz

 

 

 

 

 

 

 

 

Space: 2,000,000.00 Hz

Data

-10.0 dBm

 

 

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 5.25-1: Data Modulation mode display

1. Baud Rate

2

5

In this field enter the frequency at which the data bits will modulate the output carrier. You may enter from 0 Hz to 130,000 Hz in 1 Hz steps.

The baud rate frequency is accurate to 1 Hz from 0 Hz to 3900 Hz. It is accurate to within 1% across its full range of 0 Hz to 130,000 Hz.

2. Mark Frequency

When the modulation data bit is a 1, the output is set to the Mark frequency. You may enter a frequency from 0 Hz (DC) to 21.5 MHz in 0.01 Hz steps.

3. Space Frequency

When the modulation data bit is a 0, the output is set to the Space frequency. You may enter a frequency from 0 Hz (DC) to 21.5 MHz in .01 Hz steps.

4. Data

This word appears when a valid modulation data message has been downloaded to the 4070A. Without a valid data message, the word “Data” does not appear and the 4070A operates in regular Internal FSK mode.

5. Level

In this field enter the output level, from 4 mVp -p to 10 Vp -p in 1 mV steps or from -44.0 dBm to +24.0 dBm in 0.1 dBm steps.

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BK Precision 4070A User Manual Rev.2.2

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Contents User’s Manual Page +K Precision Corp Model 4070A User’s ManualTable of Contents Remote operation Warranty informationArbitrary waveform system DC Operation OptionIntroduction Description Modes Feature summarySIG Out connector Installation and setupSync out connector External Modulation In connector External Trigger/Gating/FSK/BPSK input External Arb Sync In / Out connector External Reference Input / Ext Arb. Clock connectorRS232 Interface connector Line in connectorOperating controls and keys Mode keyField arrow keys Recall / Store keyÉ, ê, è, ç keys Trigger keyNumeric keys 0 to 9, MHz/dBm, KHz/Vp-p/Sec, Hz/mVp-p/mS keys One Touch Mode KeysClear key Operating guide Operating mode selectionChanging frequency Changing levelEntering a new value Changing valuesModifying an existing value Sinewave Mode 000,000.00 Hz 10.0 dBm Mode descriptionsBasic Sinewave CW Mode Internal AM Mode External AM Mode Parameters External AM ModeExternal AM Input gain 000,000.00 Hz PEP level -10.0 dBm Input GainInternal FM Mode Parameters Internal FM ModeInt FM 1,000 Hz Pk dev 10,000 Hz 000,000.00 Hz 10.0 dBm Peak Frequency DeviationExternal FM Pk dev 10,000 Hz 000,000.00 Hz 10.0 dBm External FM ModeExternal FM Mode Parameters Internal PM Mode Parameters Internal PM ModePeak Phase Deviation Int PM 1,000 Hz Pk dev 180 deg 000,000.00 Hz 10.0 dBmExternal PM Pk dev 180 deg 000,000.00 Hz 10.0 dBm External PM ModeExternal PM Mode Parameters Sweep Mode Sweep time Up / Down sweepInternal FSK Mode Parameters Internal FSK ModeMark Frequency Space FrequencyExternal FSK Mode Parameters External FSK ModeExt FSK Mark 1,000,000.00 Hz Space 2,000,000.00 Hz 10.0 dBm Ext FSK InputBurst frequency Burst Mode IntroductionBurst Mode Trig Ton 10,000 mS 000,000.00 Hz Off 10.0 dBm Internal SSB Mode Parameters Internal SSB ModeInt SSB 1,000 Hz Upper Sideband 000,000.00 Hz 10.0 dBm Upper/Lower Sideband selectionsExternal SSB Upper Sideband 000,000.00 Hz +10.0 dBm External SSB ModeExternal SSB Mode Parameters Dtmf generation # Duration 200 mS Delay Level -10.0 dBm Dtmf Generation ModeDtmf Generation Mode Parameters BackgroundDtmf Duration Dtmf DelayDtmf Detection Mode Parameters Dtmf Detection ModeDtmf detection on Ext Mod input 3 # a Dtmf detected digitsPower & Voltage Measurement Mode Parameters Power & Voltage Measurement ModePower Level Voltage LevelOther mode Arbitrary ModeRemote Mode Int Bpsk 1,000 Hz 000,000.00 Hz 10.0 dBm Internal Bpsk ModeInternal Bpsk Mode Parameters External Bpsk 000,000.00 Hz 10.0 dBm External Bpsk ModeExternal Bpsk Mode Parameters 10,000 Hz F2 Ton 000 mS Toff 10.0 Dualtone Generation ModeDualtone Examples Using the Data Modulation Mode Data Modulation ModeData Modulation Mode Parameters Baud RateExample Message Downloading Modulation Message DataSaving the Message Triggering the TransmissionVCO Mode Parameters Voltage Controlled Oscillator VCO ModeStart End 1,000,000.00 Hz 10.0 dBm End FrequencyChecking your connection with Hyper Terminal ConnectingRemote Operation Remote Control Programming Rules Remote Control OperationReset 4070A to Sine wave mode Remote Control Commands× Ø Returns CReport hardware and software versions K1.0 Enable, Disable front panel keys and rotary knobE1,0 Enable, Disable LCD echo to terminal F0-9 Move cursor to field 0 to Linear Trig Up Time 10,000 mS? or H Print help menu Return a CExample Remote Control ExamplesPin 9-pin cable Pin 25 pin cable adapter Arbitrary Waveform ModeQuick Start Guide Description of the Arbitrary Waveform Generator Introduction to the Arbitrary Waveform SystemFeature Summary Switching ModesFunction Generator Pulse GeneratorInt Clock / Ext Clock / Lock Master Lock slave mode Arbitrary Waveform ModePhase Continuous/Triggered modeFunction Gen Wave Pos Ramp Rep Freq 100,000 Hz 000 mV Function Generator ModeWaveform Repetition FrequencyDuty Cycle Pulse Generator ModePositive Only Downloading arbitrary waveforms Using WAVELOAD.EXESaving Arbitrary Waveforms Cwaveload /COMx /y /baudz filename.extUsing your own program Rules for Floating Point format Data FormatsFloating Point Format Example #2 Time & Value Floating Point FormatDigital Format Integer Format Example The data value E468 is handled as follows Hexadecimal FormatRules for Hexadecimal format Example Binary FormatRules for Binary format Generator Multiple Units LockingArb Phase Resolution More on Phase OffsetsStarting Address = Number of waveform points * Phase Offset Waveform Size RestrictionsProgram Listing ARB.BAS Example Arb ProgramClose System Subroutines Return Print #1, a Send integer value to 4070A Return Return DC Operation Option Wiring DiagramOperating Modes 4070A SpecificationsRemote Software CDAppendix a Hardware SetupCLS CLS Print Print Subroutines END SUB Appendix B Television Remote Control ExampleCLS Make sure a 4070A is attached to the serial port Print Limited Two-Year Warranty Service Information Savi Ranch Pkwy Yorba Linda, CA 92887 USA TEL